HOTTIP and nasopharyngeal carcinoma: HOTTIP was highly expressed in NPC serum and cells compared with the control group; serum HOTTIP expression in NPC patients after treatment was significantly lower than that before treatment; Kaplan-Meier survival curve revealed that the Progression-Free Survival (PFS) and Overall Survival (OS) of the HOTTIP low-expression group were both better than those of the HOTTIP high-expression group; COX proportional hazard models showed that high HOTTIP expression was an independent risk factor for PFS in NPC patients.